1. Field of Invention
Embodiments described generally relate to composite structures comprising thermoplastic vulcanizates and articles made therefrom.
2. Description of Related Art
Thermoplastic vulcanizates (TPVs) may be characterized by finely divided rubber particles dispersed within a plastic matrix. These rubber particles are crosslinked to promote elasticity. As such, TPVs exhibit the processing properties of the plastic and the elasticity of the rubber.
TPVs are conventionally produced by dynamic vulcanization. Dynamic vulcanization is a process whereby a rubber component is crosslinked or vulcanized within a blend of at least one non-vulcanizing polymer component while undergoing mixing or masticating at some elevated temperature. Preferably, the temperature of this curing step is greater than the melt temperature of the non-vulcanizing polymer component.
TPVs have been used to form composite structures for use in automotive, industrial, and consumer markets. Some of those uses require the adhesion of a TPV component to other materials to form a completed structure. Sufficient adhesion of which is difficult to obtain and difficult to maintain depending on the materials to be adhered, the adhering conditions, as well as the environment or conditions of use. For example, WO 02/051634 discloses a two component composite structure where one of the polymer structures is made of EPDM blended with an effective amount of semicrystalline random adhesive copolymer, and the other polymer structure is made of a blend of dynamically vulcanized EPDM dispersed in a matrix of a thermoplastic polyolefin polymer. WO 02/051634 also discloses that the second polymer structure may be blended with the semicrystalline random adhesive copolymer. EP 0 601 790 discloses a two-layer sheet where each layer is made from an alpha olefin copolymer rubber and a polyolefin resin. The first layer or “skin layer” is partially crosslinked, and the second layer or “back surface layer” is non-crosslinked. EP 0 601 790 discloses that the polyolefin resin is a homopolymer of ethylene or propylene, or copolymers of ethylene or propylene with small amounts of other polymeric monomers.